using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using ProjectI.Builds;
using ProjectI.Combat;
using ProjectI.Menu;
using ProjectI.Runs;
using UnityEngine;
using UnityEngine.UIElements;

namespace ProjectI.UI
{
    public sealed class CoreRewardView : IDisposable
    {
        public VisualElement Panel { get; }
        public Label Heading { get; }
        public Label Status { get; }
        public Toggle Details { get; }
        public ScrollView CardScroll { get; }
        public VisualElement Cards { get; }
        public Button Confirm { get; }
        private readonly Label team,buildText,footerHint,offerTitle,remaining,localStatus,buildContext;
        private readonly Button inspect;
        private readonly ScrollView inspection;
        private readonly VisualElement installed;
        private readonly Action confirmAction,inspectionAction;
        private string inventoryIdentity="";
        public bool InspectionOpen { get; private set; }
        public CoreRewardView(VisualElement parent,Action confirm,Action inspectBuild)
        {
            confirmAction=confirm;inspectionAction=inspectBuild;
            Panel=new VisualElement {name="upgradeChoicePanel"};Panel.AddToClassList("run-panel");Panel.AddToClassList("upgrade-choice-panel");Panel.AddToClassList("core-reward-shell");Panel.AddToClassList("hidden");parent.Add(Panel);
            var header=new VisualElement();header.AddToClassList("core-reward-header");Panel.Add(header);
            Label(header,"INDIE FPS ROGUELIKE / STAGE TRANSITION","core-reward-eyebrow");
            Heading=Label(header,"Choose a core","run-heading");Label(header,"Stage transition / run-only upgrades","core-reward-subtitle");
            var body=new VisualElement();body.AddToClassList("core-reward-body");Panel.Add(body);
            var main=new VisualElement();main.AddToClassList("core-reward-main");body.Add(main);
            var aside=new VisualElement();aside.AddToClassList("core-reward-team");body.Add(aside);
            Label(aside,"TEAM PROGRESS","core-reward-eyebrow");team=Label(aside,"","core-team-progress");team.name="rewardTeamProgress";
            Label(aside,"You","core-team-owner");localStatus=Label(aside,"Choosing a core","core-team-local");localStatus.name="rewardLocalStatus";
            Label(aside,"Travel begins when everyone has completed their choices.","core-reward-subtitle");
            var offerRow=new VisualElement();offerRow.AddToClassList("core-offer-heading");main.Add(offerRow);
            offerTitle=Label(offerRow,"SELECT ONE CORE","core-reward-eyebrow");offerTitle.name="rewardOfferTitle";remaining=Label(offerRow,"","core-choice-count");remaining.name="rewardChoiceCount";
            var toolbar=new VisualElement();toolbar.AddToClassList("core-reward-toolbar");
            Details=new Toggle("Details / stack difference (or hold Shift)"){name="coreDetailsToggle"};toolbar.Add(Details);
            inspect=new Button(ToggleInspection){text="+ Inspect current build and installed cores",name="inspectRewardBuild"};toolbar.Insert(0,inspect);
            CardScroll=new ScrollView(ScrollViewMode.Vertical){name="upgradeCardsScroll"};CardScroll.AddToClassList("upgrade-card-scroll");main.Add(CardScroll);
            Cards=new VisualElement {name="upgradeCards"};Cards.AddToClassList("upgrade-cards");CardScroll.Add(Cards);
            buildContext=Label(main,"Your run abilities stay equipped. Only compatible cores enter the offer.","core-reward-context");buildContext.name="rewardEquippedContext";main.Add(toolbar);
            inspection=new ScrollView(ScrollViewMode.Vertical){name="rewardBuildInspection"};inspection.AddToClassList("core-reward-inspection");inspection.AddToClassList("hidden");main.Add(inspection);
            buildText=Label(inspection,"","core-build-text");Label(inspection,"INSTALLED CORES · current ranks","core-inspection-heading");
            installed=new VisualElement();installed.AddToClassList("inspection-grid");inspection.Add(installed);
            var footer=new VisualElement();footer.AddToClassList("core-reward-footer");main.Add(footer);var footerCopy=new VisualElement();footerCopy.AddToClassList("core-footer-copy");footer.Add(footerCopy);footerHint=Label(footerCopy,"Inspecting a card does not spend the core.","core-reward-subtitle");footerHint.name="coreRewardHint";
            Status=Label(footerCopy,"Select a card to preview its effect.","upgrade-choice-status");Status.AddToClassList("run-wrap");
            Confirm=new Button(confirmAction){text="Confirm core",name="upgradeNext"};Confirm.AddToClassList("upgrade-next-button");Confirm.SetEnabled(false);footer.Add(Confirm);
            Panel.RegisterCallback<KeyDownEvent>(OnKeyDown);
            Panel.RegisterCallback<GeometryChangedEvent>(OnGeometry);
        }
        private static Label Label(VisualElement parent,string text,string css)
        {var label=new Label(text){pickingMode=PickingMode.Ignore};label.AddToClassList(css);parent.Add(label);return label;}
        public void BindHeader(string heading,string localStatus,int complete,int participants)
        {Heading.text=heading=="CHOOSE A CORE"?"Choose a core":heading=="CORE INSTALLED"?"Core installed":heading=="CHOOSE A CATEGORY"?"Choose a category":heading=="CHOICES COMPLETE"?"Choices complete":heading;Status.text=localStatus;team.text=$"{Math.Max(0,Math.Min(complete,participants))} / {participants} complete";}
        public void BindFooter(CoreOfferKind kind,bool exhausted=false)
        {footerHint.text=kind==CoreOfferKind.Category?(exhausted?"Keep this core for the next stage when no compatible award is available.":"Choosing a category awards one random compatible core immediately."):kind==CoreOfferKind.AwardReceipt?"This core is installed. Continue to finish reviewing it.":kind==CoreOfferKind.Specific?"Inspecting a card does not spend the core.":"Inspect your current build while waiting for the team.";}
        public void BindOfferContext(CoreOfferKind kind,UpgradeTier? tier,int pending,string equipped,string ownerStatus)
        {offerTitle.text=kind==CoreOfferKind.AwardReceipt?"INSTALLED CORE":kind==CoreOfferKind.None?(pending>0?"PREPARING NEXT CORE":"CHOICES COMPLETE"):(tier.HasValue?tier.Value.ToString().ToUpperInvariant()+" CORE · ":"")+(kind==CoreOfferKind.Category?"CHOOSE A CATEGORY":"SELECT ONE");remaining.text=pending==1?"1 choice remaining":Math.Max(0,pending)+" choices remaining";localStatus.text=ownerStatus;buildContext.text=string.IsNullOrEmpty(equipped)?"Your run abilities stay equipped. Only compatible cores enter the offer.":"Equipped: "+equipped+". Only compatible cores enter the offer.";}
        private void OnGeometry(GeometryChangedEvent value)=>Panel.EnableInClassList("core-reward-short",Panel.worldBound.height<600);
        private void ToggleInspection()
        {SetInspection(!InspectionOpen);if(InspectionOpen){inspectionAction?.Invoke();inspection.Focus();}else inspect.Focus();}
        private void SetInspection(bool open)
        {InspectionOpen=open;Panel.EnableInClassList("core-inspecting",open);inspection.EnableInClassList("hidden",!open);CardScroll.EnableInClassList("hidden",open);inspect.text=open?"− Inspect current build and installed cores [Esc]":"+ Inspect current build and installed cores";}
        private void OnKeyDown(KeyDownEvent value)
        {if(value.keyCode==KeyCode.Escape&&InspectionOpen){CloseInspection();value.StopImmediatePropagation();}}
        public void CloseInspection(){SetInspection(false);inspect.Focus();}
        public void OpenInspection(){SetInspection(true);inspection.Focus();}
        public void ResetInspection(){SetInspection(false);inventoryIdentity="";installed.Clear();buildText.text="";}
        public void BindInspection(PrototypePlayerCombat player,IReadOnlyList<UpgradeInventoryEntry> inventory)
        {
            if(player==null)return;
            var definitions=player.AbilityDefinitions.Where(d=>d!=null).ToDictionary(d=>d.id,d=>d);
            var text=new StringBuilder($"CURRENT RUN BUILD · read only\nHP {player.Vitals.CurrentHealth:0.#} / {player.Vitals.MaximumHealth:0.#} · shield {player.Vitals.Shield:0.#} / {player.Vitals.MaximumShield:0.#} · overshield {player.Vitals.Overshield:0.#}\nWalk {player.MovementSpeed:0.##} m/s · gun {player.AttackDamageMultiplier:0.##}× · ability {player.AbilityDamageMultiplier:0.##}×\nAbilities stay equipped during this run.\n");
            foreach(LibrarySlot slot in Enum.GetValues(typeof(LibrarySlot)))
            {
                int id=AbilityLibraryState.EquippedId(player.Loadout,slot);if(!definitions.TryGetValue(id,out var d))continue;
                text.AppendLine($"\n{slot} · {d.displayName}\n{AbilityLibraryPresentation.Summary(d)}");
            }
            string identity=player.Vitals.MaximumHealth+"|"+player.Vitals.MaximumShield+"|"+string.Join(";",(inventory??Array.Empty<UpgradeInventoryEntry>()).Select(x=>$"{x.UpgradeId},{x.AbilityId},{x.Rank}"));
            buildText.text=text.ToString();if(identity==inventoryIdentity)return;inventoryIdentity=identity;installed.Clear();
            foreach(var entry in inventory??Array.Empty<UpgradeInventoryEntry>())
            {
                AddInstalledTile(entry,new CoreDisplayContext(player.Vitals.MaximumHealth,player.Vitals.MaximumShield,CoreRewardPresentation.TargetLabel(entry.AbilityId,player.Loadout,definitions)));
            }
            if(installed.childCount==0)Label(installed,"No cores installed yet.","core-build-text");
        }
        public void ShowInspectionContent(string summary,IReadOnlyList<UpgradeInventoryEntry> inventory,CoreDisplayContext context)
        {
            buildText.text=summary;installed.Clear();
            foreach(var entry in inventory??Array.Empty<UpgradeInventoryEntry>())
            {AddInstalledTile(entry,context);}
            if(installed.childCount==0)Label(installed,"No cores installed yet.","core-build-text");
        }
        private void AddInstalledTile(UpgradeInventoryEntry entry,CoreDisplayContext context)
        {
            var tile=CoreInspectionPanel.CreateInstalledTile(entry,context);installed.Add(tile);
            var formatted=UpgradeCardFormatter.Format((UpgradeId)entry.UpgradeId,entry.Rank,context,CorePresentationMode.Installed);
            Label(tile,entry.Tier+" · rank "+entry.Rank+(entry.AbilityId>0?"\n"+context.AbilityName:""),"core-card-target");
            var detail=Label(tile,formatted.Secondary+"\n"+formatted.Details,"core-installed-detail");detail.AddToClassList("hidden");
            Action expand=()=>{detail.RemoveFromClassList("hidden");tile.schedule.Execute(()=>inspection.ScrollTo(tile)).ExecuteLater(1);};
            tile.clicked+=expand;tile.RegisterCallback<FocusInEvent>(_=>expand());
        }
        public CompactCoreCard CreateCard(int id,UpgradeTier tier,long rank,bool awarded,string target,Action activate)
        {
            var view=new CompactCoreCard(id,tier,awarded?"Installed":"Select core",activate);view.EnableRewardPresentation();
            view.SetRewardMetadata(CoreRewardPresentation.RankTransition(rank,awarded),target=="Global core"?"Applies · your build":"Target · "+target);
            if(awarded){view.Action.SetEnabled(false);view.Action.style.display=DisplayStyle.None;}
            view.Action.RegisterCallback<FocusInEvent>(_=>CardScroll.ScrollTo(view.Action));Cards.Add(view);return view;
        }
        public void ShowSpecific(UpgradeOffer offer,CoreDisplayContext context,Action<UpgradeCard> select)
        {
            BindFooter(CoreOfferKind.Specific);
            Cards.Clear();foreach(var card in offer.Cards??Array.Empty<UpgradeCard>())
            {var view=CreateCard(card.UpgradeId,card.Tier,card.CurrentRank,false,context.AbilityName,()=>select(card));view.Bind(UpgradeCardFormatter.Format((UpgradeId)card.UpgradeId,card.CurrentRank,context,CorePresentationMode.Next),Details.value);}
        }
        public void ShowCategory(CoreCategoryOffer offer,Action<CoreCategory> select,Action defer)
        {BindFooter(CoreOfferKind.Category,offer.Exhausted);Cards.Clear();Cards.Add(new CoreCategoryView(offer,select,defer,true));Confirm.style.display=DisplayStyle.None;Details.style.display=DisplayStyle.None;}
        public void ShowReceipt(CoreAwardReceipt receipt,CoreDisplayContext context)
        {BindFooter(CoreOfferKind.AwardReceipt);Cards.Clear();var card=CreateCard(receipt.UpgradeId,receipt.Tier,receipt.NewRank,true,context.AbilityName,()=>{});card.Bind(UpgradeCardFormatter.Format((UpgradeId)receipt.UpgradeId,receipt.NewRank,context,CorePresentationMode.Awarded),Details.value);Confirm.text="Continue";Confirm.SetEnabled(true);}
        public void SetAwaiting(bool awaiting,string actionText){Confirm.text=actionText;Confirm.SetEnabled(!awaiting);}
        public void ShowWaiting(string reason){BindFooter(CoreOfferKind.None);Cards.Clear();Status.text=reason;Confirm.SetEnabled(false);Details.style.display=DisplayStyle.None;}
        public void Dispose(){Panel.UnregisterCallback<KeyDownEvent>(OnKeyDown);Panel.UnregisterCallback<GeometryChangedEvent>(OnGeometry);Confirm.clicked-=confirmAction;inspect.clicked-=ToggleInspection;Panel.RemoveFromHierarchy();}
    }
}